Q: How did you both get involved in the LSST project?
Schneider: We both study growing supermassive black holes in the universe. I was also involved in an early digital sky survey, the Sloan Survey, which was the original conception for the LSST survey.
Brandt: I got interested in the project in 2004. The prospects of revolutionary scientific discoveries across a very wide area of astrophysics, ranging from the solar system through to the galaxy, through to the extragalactic universe, through to dark matter and dark energy—all from a single survey—seemed exciting. We both pushed for the department to get involved around 2005.
Q: Tell us about the Rubin Observatory, where the project is located.
Brandt: It’s named after Vera Rubin, a pioneering astronomer and a brilliant scientist who was very interested in looking at galaxies. It’s located in the Coquimbo region of Chile, one of the best sites in the world for a telescope because the air is so steady. In 2010, Rubin was ranked No. 1 among ground-based projects for astronomers. COVID-19 delayed the project, of course, but ultimately things worked out, and now we have this wonderful observatory that conducts an astronomical survey of the southern sky.
Q: So there’s a telescope and there’s a camera—which you say is the largest digital camera ever built. Just how big is it?
Schneider: The typical iPhone camera contains 12 megapixels. The LSST camera is the size of a car and has 3.2 gigapixels—that’s equivalent to 267 iPhone cameras. Its focal plane has a diameter of 64 centimeters, slightly over 2 feet. It sits inside a telescope with an 8-meter diameter, which is inside a 1,600-ton dome. And every image the camera takes covers an area equivalent to 45 full moons.
Q: Tell us more about the actual photos that the camera takes—the first set of which was released last June.
Brandt: For 10 years, the camera will survey most of the southern sky every few nights with 30-second exposures to create an ultrawide, ultrahigh-definition time-lapse record of the universe. There’ll be images of all kinds of things—quasars, supermassive black holes, supernovae.
Schneider: We’ll see things going “kaboom” that we had no idea existed. What’s particularly exciting for these transient sources is that scientists will have nearly real-time access to the data.
Niel Brandt is the Eberly Family Chair Professor of Astronomy and Astrophysics.
Donald Schneider is a Distinguished Professor of Astronomy and Astrophysics.
